public MeshResult SplitEdge(int eab, out EdgeSplitInfo split)
{
split = new EdgeSplitInfo();
if (!IsEdge(eab))
{
return(MeshResult.Failed_NotAnEdge);
}
// look up primary edge
int eab_i = 3 * eab;
int a = edges[eab_i], b = edges[eab_i + 1];
int gid = edges[eab_i + 2];
// create new vertex
int f = append_new_split_vertex(a, b);
// rewrite edge bc, create edge af
int eaf = eab;
replace_edge_vertex(eaf, b, f);
vertex_edges[b].Remove(eab);
vertex_edges[f].Add(eaf);
// create new edge fb
int efb = add_edge(f, b, gid);
// update vertex refcounts
vertices_refcount.increment(f, 2);
split.vNew = f;
split.eNewBN = efb;
updateTimeStamp(true);
return(MeshResult.Ok);
}
public MeshResult SplitEdge(int vA, int vB, out EdgeSplitInfo split)
{
int eid = find_edge(vA, vB);
if (eid == InvalidID)
{
split = new EdgeSplitInfo();
return(MeshResult.Failed_NotAnEdge);
}
return(SplitEdge(eid, out split));
}
public MeshResult SplitEdge(int eab, out EdgeSplitInfo split)
{
split = new EdgeSplitInfo();
if (!IsEdge(eab))
{
return(MeshResult.Failed_NotAnEdge);
}
// look up primary edge
int eab_i = 3 * eab;
int a = edges[eab_i], b = edges[eab_i + 1];
int gid = edges[eab_i + 2];
// create new vertex
Vector2d vNew = 0.5 * (GetVertex(a) + GetVertex(b));
Vector3f cNew = (HasVertexColors) ? (0.5f * (GetVertexColor(a) + GetVertexColor(b))) : Vector3f.One;
int f = AppendVertex(vNew, cNew);
// rewrite edge bc, create edge af
int eaf = eab;
replace_edge_vertex(eaf, b, f);
vertex_edges[b].Remove(eab);
vertex_edges[f].Add(eaf);
// create new edge fb
int efb = add_edge(f, b, gid);
// update vertex refcounts
vertices_refcount.increment(f, 2);
split.vNew = f;
split.eNewBN = efb;
updateTimeStamp(true);
return(MeshResult.Ok);
}
public MeshResult SplitEdge(int eab, out EdgeSplitInfo split)
{
split = new EdgeSplitInfo();
if (!IsEdge(eab))
{
return(MeshResult.Failed_NotAnEdge);
}
// look up primary edge & triangle
int eab_i = 4 * eab;
int a = edges[eab_i], b = edges[eab_i + 1];
int t0 = edges[eab_i + 2];
if (t0 == InvalidID)
{
return(MeshResult.Failed_BrokenTopology);
}
Index3i T0tv = GetTriangle(t0);
int[] T0tv_array = T0tv.array;
int c = IndexUtil.orient_tri_edge_and_find_other_vtx(ref a, ref b, T0tv_array);
// create new vertex
Vector3d vNew = 0.5 * (GetVertex(a) + GetVertex(b));
int f = AppendVertex(vNew);
// quite a bit of code is duplicated between boundary and non-boundary case, but it
// is too hard to follow later if we factor it out...
if (edge_is_boundary(eab))
{
// look up edge bc, which needs to be modified
Index3i T0te = GetTriEdges(t0);
int ebc = T0te[IndexUtil.find_edge_index_in_tri(b, c, T0tv_array)];
// rewrite existing triangle
replace_tri_vertex(t0, b, f);
// add new second triangle
int t2 = add_triangle_only(f, b, c, InvalidID, InvalidID, InvalidID);
if (triangle_groups != null)
{
triangle_groups.insert(triangle_groups[t0], t2);
}
// rewrite edge bc, create edge af
replace_edge_triangle(ebc, t0, t2);
int eaf = eab;
replace_edge_vertex(eaf, b, f);
vertex_edges[b].Remove(eab);
vertex_edges[f].Add(eaf);
// create new edges fb and fc
int efb = add_edge(f, b, t2);
int efc = add_edge(f, c, t0, t2);
// update triangle edge-nbrs
replace_triangle_edge(t0, ebc, efc);
set_triangle_edges(t2, efb, ebc, efc);
// update vertex refcounts
vertices_refcount.increment(c);
vertices_refcount.increment(f, 2);
split.bIsBoundary = true;
split.vNew = f;
split.eNew = efb;
updateTimeStamp(true);
return(MeshResult.Ok);
}
else // interior triangle branch
// look up other triangle
{
int t1 = edges[eab_i + 3];
Index3i T1tv = GetTriangle(t1);
int[] T1tv_array = T1tv.array;
int d = IndexUtil.find_tri_other_vtx(a, b, T1tv_array);
// look up edges that we are going to need to update
// [TODO OPT] could use ordering to reduce # of compares here
Index3i T0te = GetTriEdges(t0);
int ebc = T0te[IndexUtil.find_edge_index_in_tri(b, c, T0tv_array)];
Index3i T1te = GetTriEdges(t1);
int edb = T1te[IndexUtil.find_edge_index_in_tri(d, b, T1tv_array)];
// rewrite existing triangles
replace_tri_vertex(t0, b, f);
replace_tri_vertex(t1, b, f);
// add two new triangles to close holes we just created
int t2 = add_triangle_only(f, b, c, InvalidID, InvalidID, InvalidID);
int t3 = add_triangle_only(f, d, b, InvalidID, InvalidID, InvalidID);
if (triangle_groups != null)
{
triangle_groups.insert(triangle_groups[t0], t2);
triangle_groups.insert(triangle_groups[t1], t3);
}
// update the edges we found above, to point to new triangles
replace_edge_triangle(ebc, t0, t2);
replace_edge_triangle(edb, t1, t3);
// edge eab became eaf
int eaf = eab; //Edge * eAF = eAB;
replace_edge_vertex(eaf, b, f);
// update a/b/f vertex-edges
vertex_edges[b].Remove(eab);
vertex_edges[f].Add(eaf);
// create new edges connected to f (also updates vertex-edges)
int efb = add_edge(f, b, t2, t3);
int efc = add_edge(f, c, t0, t2);
int edf = add_edge(d, f, t1, t3);
// update triangle edge-nbrs
replace_triangle_edge(t0, ebc, efc);
replace_triangle_edge(t1, edb, edf);
set_triangle_edges(t2, efb, ebc, efc);
set_triangle_edges(t3, edf, edb, efb);
// update vertex refcounts
vertices_refcount.increment(c);
vertices_refcount.increment(d);
vertices_refcount.increment(f, 4);
split.bIsBoundary = false;
split.vNew = f;
split.eNew = efb;
updateTimeStamp(true);
return(MeshResult.Ok);
}
}